Here are a few interesting ideas you may consider playing around with.....

A) Consider interfacing an 8052 to an RC (RF remote control) receiver. Setup some kind of application that the user can use RC transmitter joy sticks to open and close a window. Have the 8052 provide the connection to running the servo and linkage to window. Next implement two temperature sensors, one for outside the window and one inside the window. Have the software provide an algorithm to automatically open and close the window to cool and/or keep warm the room of the house. I.E. The window will have both manual remote control and automatic control.

B) Make an 8051 system that has a processor on a battery that can collect some kind of analog data over time like a small data logging function. (Temperature may be one thing to measure). Then provide the 8051 with a specialized serial interface to connect to a TI-86 graphing calculator remote jack and make the 8051 able to transfer its data log to the calculator. Have the calculator setup with a scrolling (chart recorder) type display to continuously display the 8051 data log in real time.

3) Program an 8051 to have an output that simulates the output of a computer mouse. Connect the mouse simulator to a PC such that the programming inside your 8051 is able to move the computer cursor around and activate the mouse button inputs. Then consider some aspect of how a handicapped person has difficulty using the computer mouse in the normal way. Devise a scheme of some sort that the handicapped person can activate "mouse like" functions in an alternate manner. Input those signals to your 8051 and have its software translate the inputs to mouse sequences that the PC can understand. (For example maybe a person with no arms can learn to push on two rollers (one for X and one for Y) with their feet.

I know that some of these ideas may already be commercially available....but that is of no real concern because your project is more about tackling a problem from an engineering prespective and coming up with a solution.

Have Fun !!!
Mike Karas